/**
 * Copyright 2008 Mathias Doenitz, http://lis.to/
 *
 * This file is part of the lis.to java desktop client. The lis.to java desktop client is free software: you can
 * redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free
 * Software Foundation, either version 3 of the License, or (at your option) any later version.
 *
 * The lis.to java desktop client is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with the lis.to java desktop client.
 * If not, see http://www.gnu.org/licenses/
 */

package listo.client.dialogs.autocompletion;

import listo.utils.swing.AutoCompleter;
import org.apache.commons.lang.StringUtils;

import java.util.ArrayList;
import java.util.List;

public abstract class BaseCompleter implements AutoCompleter.CompletionProvider {

    protected final List<String> availableOptions = new ArrayList<String>();

    // default for completion providers
    public boolean isWordSeparator(char c) {
        return false;
    }

    // default implementation
    public void provideAutoCompletion(AutoCompleter.Context context) {
        if (context.getEventType() != AutoCompleter.EventType.TextTyped) {
            context.getOptions().addAll(availableOptions);
            return;
        }
        for (String option : availableOptions) {
            String lowOption = option.toLowerCase();
            if (lowOption.equals(context.getCurrentWordTrimmedLower())) {
                context.getOptions().clear();
                return;
            }
            if (lowOption.startsWith(context.getCurrentWordTrimmedLower())) {
                context.getOptions().add(option);
            }
        }
    }

    /**
     * Returns the best match for the given word from the given options.
     *
     * @param word    the word
     * @param options the options
     * @return the best match
     */
    protected static int bestMatch(String word, List<String> options) {
        int bestMatch = -1;
        int minDistance = Integer.MAX_VALUE;
        for (int i = 0; i < options.size(); i++) {
            String option = options.get(i);
            if (option.equals(word)) return i;
            int distance = StringUtils.getLevenshteinDistance(option, word);
            if (distance < minDistance) {
                minDistance = distance;
                bestMatch = i;
            }
        }
        return bestMatch;
    }

}
